Metal Compounds in the Development of Antiparasitic Agents: Rational Design from Basic Chemistry to the Clinic.

Metal compounds seem to be a promising approach in the search of new therapeutic solutions for neglected tropical diseases. In this chapter, efforts in the design of prospective metal-based drugs for the treatment of Chagas disease, human African trypanosomiasis, and leishmaniasis are discussed. Careful selection of the metal center (including organometallic cores) and the types and number of coordinated ligands is essential for controlling the reactivity of the complexes and hence, tuning their biological properties. In a target-based approach, some targets that have been validated for organic antiparasitic compounds are expected to remain targets for metal complexes of these compounds. In addition, specific targets for metal compounds, like parasitic enzymes or DNA, would also be included for these metal complexes leading to potential additive or even synergistic effects between organic ligand and metal ion. However, even though a good number of prospective antiparasitic metal-based drugs have been developed, further systematic efforts are needed for these metal compounds to accomplish the regulatory guidelines that let them reach the different stages of clinical trials.